Mysterious knocking noise
 

There is a strange knocking noise comming from (i think) the front passenger side wheel whenever i accelerate, brake, or go over a manhole cover or other bump on that side of the car. This noise manifested itself once before but on the drivers side, and it went away after a while. I am going to take it to my mechanic tomorrow to see if they can determine the cause, but the last time it happened, they could not find anything wrong. Has anyone else had this issue, or know anything about it?

This kind of sounds like a bad Strut Bearing. The mount where the 3 screws are at the top of your Strut. The bearings allow the Strut to turn with the wheel. When they go bad, they can be noisy when turning the wheel left or right, like a rough grinding sound, or make No noise at all. Or when driving over a bumpy road it sounds like Something metal is hitting the inside of you wheel well. Making small bumps sound like Big ones and Big ones sound like your tire just got ripped off your car.
It can be replaced But you would have to remove your Strut and have a spring compressor.
Unless you work in a shop I don't recommend doing this because of the massive pressure the springs are under. I've seen a Mechanic get hit in the face with a spring. It wasn't pretty at all.
If you are going to do it yourself I recommend getting Quick Struts. It's a New Strut, spring and bearing, pre assembled so all you have to do is remove the old Strut and put the new one in. 5 BOLTS.
To check your struts you need to either give the car a Big bounce, or have it checked by your mechanic.
Other things it could be, Hub bearing, bad Strut, bad suspension bushings. I Hope this helps. Good Luck and Safe Driving!

thanks a lot for the info! I just had my shocks/struts/springs replaced a couple weeks ago, so i would be very surprised if it's part of that assembly. It's not really a grinding noise, more like somebody is lightly tapping something solid with a hammer. Maybe it's the hub, like you said. Hopefully i will find out for sure at the shop tomorrow. Thank you again!

Check the bolt at the top of your Strut piston. I did Quick struts on my wife's Lexus. They were fine for about 2 weeks. Then I started getting that same type of tapping in the rear right Strut. When I checked it I found that the Strut piston bolt was loose and t the piston was moving with the Strut instead of with the car. I tightened the bolt up torqued it down and wa-la night more tapping!

I had the same thing happening! Only mine was on the driver side. It was my caliper. Somehow my caliper came lose. So I tightened the bolts and now the noise is gone!

Well, i sure feel kinda dumb now. Relieved, but dumb. I recently installed the shorter dogbones from ZZP, and it turns out that they were hitting against the motor mounts. Not exactly a direct fit. But with a little grinding, my mechanic was able to get them fitting perfect now, and no more knocking.

Have you lowered your car?? The shorter dog bones are to help with engine/trans positioning when someone lowers there car.

If you have not, you may want to consider going back to the stock dog bones.

Yes, i do have it lowered. Just had it done a few weeks ago. I was noticing some vibration, especially at WOT, and went on ZZP and saw that the dogbones would fix that problem as well as minimize the axle angle to aid the trans in it's functions. Which they have done. I am pleased with the results, just the fitment wasn't quite perfect, until now.